在上两篇文章中分别讲述了通过MCU配置S2E为UDP、TCP Server的工作模式”，相信小伙伴们已经对S2E的基本功能了解了一些，现在就让我们再接再厉、更上一层楼吧：
首先我们先了解一下MCU与S2E的接线方式：
- 1、接线方式：
- 2、例程说明：
- 打开“通过MCU配置S2E为TCP Client例程”，主程序中第一部分TIM3_Init();是设定一个帧中断的时间定时器，这是因为该例程MCU的串口是通过帧中断来接收AT命令配置S2E后返回的数据的。
第二部分USARTX_Init();初始化MCU用到的串口，这里用USART1_Config();是printf功能，用于查看调试信息。USART2_Config();用于配置S2E，需要注意的是该串口的配置参数需要同S2E的串口配置参数一致，否则配置失败。
第三部分主循环中的TCP_Client_Mode();用于配置S2E为TCP Client模式。S2E的AT命令列表详见各个S2E型号的用户手册AT命令章节介绍。配置成功，串口打印“TCP Client Config Success!”，配置失败串口打印“TCP Client Config Fail!”。
/****************************************************
函数名：TCP_Client_Mode
形参：无
返回值：无
函数功能：通过串口发送AT命令配置S2E模块
****************************************************/
volatile uint8_t SendFlag = 0;
void TCP_Client_Mode(void)
{
uint8_t RecvFlag = 1;
char *state;
switch (SendFlag)
{
case 0:
{
Usart_Send(USART2, "AT\r\n"); //终端检测命令
while (RecvFlag)
{
if (RX2_Point & FRAME_LEN)
{
//如果接收到数据
state = strstr((char*) RecvBuff, "OK");
//判断回复的数据中是否有“OK”
if (state != NULL)
{
//有
RX2_Point = 0;
//接收缓冲区指针置零
RecvFlag = 0;
//接收标致位置零
SendFlag = 1; //发送标志位置零
printf("Recv:%s\r\n", RecvBuff);
memset(RecvBuff, 0, RECV_LEN);
//接收缓存清零
}
else
{
//无
SendFlag = 100; //配置失败
RecvFlag = 0;
}
}
}
}
break;
case 1:
{
Usart_Send(USART2, "AT+ECHO=0\r\n");
//开启（1）/关闭（0）回显命令
RecvFlag = 1;
while (RecvFlag)
{
if (RX2_Point & FRAME_LEN)
{
state = strstr((char*) RecvBuff, "OK");
if (state != NULL)
{
RX2_Point = 0;
RecvFlag = 0;
SendFlag = 2;
printf("Recv:%s\r\n", RecvBuff);
memset(RecvBuff, 0, RECV_LEN);
}
else
{
SendFlag = 100;
RecvFlag = 0;
}
}
}
}
break;
case 2:
{
Usart_Send(USART2, "AT+C1_OP=1\r\n"); //配置为TCP
Client模式命令
RecvFlag = 1;
while (RecvFlag)
{
if (RX2_Point & FRAME_LEN)
{
state = strstr((char*) RecvBuff, "OK");
if (state != NULL)
{
RX2_Point = 0;
RecvFlag = 0;
SendFlag = 3;
printf("Recv:%s\r\n", RecvBuff);
memset(RecvBuff, 0, RECV_LEN);
}
else
{
SendFlag = 100;
RecvFlag = 0;
}
}
}
}
break;
case 3:
{
Usart_Send(USART2, "AT+IP_MODE=1\r\n");
//配置DHCP模式命令
RecvFlag = 1;
while (RecvFlag)
{
if (RX2_Point & FRAME_LEN)
{
state = strstr((char*) RecvBuff, "OK");
if (state != NULL)
{
RX2_Point = 0;
RecvFlag = 0;
SendFlag = 4;
printf("Recv:%s\r\n", RecvBuff);
memset(RecvBuff, 0, RECV_LEN);
}
else
{
SendFlag = 100;
RecvFlag = 0;
}
}
}
}
break;
case 4:
{
Usart_Send(USART2, "AT+C1_PORT=5000\r\n");
//配置S2E的本地端口号
RecvFlag = 1;
while (RecvFlag)
{
if (RX2_Point & FRAME_LEN)
{
state = strstr((char*) RecvBuff, "OK");
if (state != NULL)
{
RX2_Point = 0;
RecvFlag = 0;
SendFlag = 5;
printf("Recv:%s\r\n", RecvBuff);
memset(RecvBuff, 0, RECV_LEN);
}
else
{
SendFlag = 100;
RecvFlag = 0;
}
}
}
}
break;
case 5:
{
Usart_Send(USART2, "AT+C1_CLI_IP1=192.168.1.109\r\n");
//配置远程服务器的IP地址
RecvFlag = 1;
while (RecvFlag)
{
if (RX2_Point & FRAME_LEN)
{
state = strstr((char*) RecvBuff, "OK");
if (state != NULL)
{
RX2_Point = 0;
RecvFlag = 0;
SendFlag = 6;
printf("Recv:%s\r\n", RecvBuff);
memset(RecvBuff, 0, RECV_LEN);
}
else
{
SendFlag = 100;
RecvFlag = 0;
}
}
}
}
break;
case 6:
{
Usart_Send(USART2, "AT+C1_CLI_PP1=5000\r\n");
//配置远程服务器的端口号
RecvFlag = 1;
while (RecvFlag)
{
if (RX2_Point & FRAME_LEN)
{
state = strstr((char*) RecvBuff, "OK");
if (state != NULL)
{
RX2_Point = 0;
RecvFlag = 0;
SendFlag = 7;
printf("Recv:%s\r\n", RecvBuff);
memset(RecvBuff, 0, RECV_LEN);
}
else
{
SendFlag = 100;
RecvFlag = 0;
}
}
}
}
break;
case 7:
{
Usart_Send(USART2, "AT+START_MODE=0\r\n");
//配置下次上电启动模式（0-AT模式，1-
数据模式）
RecvFlag = 1;
while (RecvFlag)
{
if (RX2_Point & FRAME_LEN)
{
state = strstr((char*) RecvBuff, "OK");
if (state != NULL)
{
RX2_Point = 0;
RecvFlag = 0;
SendFlag = 8;
printf("Recv:%s\r\n", RecvBuff);
memset(RecvBuff, 0, RECV_LEN);
}
else
{
SendFlag = 100;
RecvFlag = 0;
}
}
}
}
break;
case 8:
{
Usart_Send(USART2, "AT+EXIT\r\n");
//保存配置并进入数据模式
RecvFlag = 1;
while (RecvFlag)
{
if (RX2_Point & FRAME_LEN)
{
state = strstr((char*) RecvBuff, "OK");
if (state != NULL)
{
RX2_Point = 0;
RecvFlag = 0;
SendFlag = 99;
printf("Recv:%s\r\n", RecvBuff);
memset(RecvBuff, 0, RECV_LEN);
}
else
{
SendFlag = 100;
RecvFlag = 0;
}
}
}
}
break;
case 99:
{
//配置成功！
printf("TCP Client Config Success!\r\n");
Config_OK = 1;
}
default:
RecvFlag = 100;
break;
case 100:
{
//配置失败！
printf("TCP Client Config Fail!\r\n");
Config_OK = 1;
}
break;
}
}
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